Exploring Heavy Metal Bioaccumulation in Vegetables: Unraveling Environmental Pollutants' Impact on Agricultural Produce and Human Health.

Abstract

Vegetables cultivated near industrial zones are susceptible to heavy metal accumulation, posing serious food safety and public health risks. This study quantified six toxic metals (As, Cd, Cr, Ni, Pb, and Hg) in six commonly consumed vegetables-spinach, pumpkin leaf, brinjal, tomato, potato, and radish-alongside corresponding soil and irrigation water samples from Savar, Bangladesh, using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Essential micronutrients (Ca, Na, Fe, K, Cu, Mn, Zn, and Mg) were also determined via Atomic Absorption Spectrophotometry (AAS). Soil exhibited elevated Pb (19.26 ± 2.6 mg/kg) and Hg (16.92 ± 6.9 mg/kg), while irrigation water exceeded WHO limits for Pb (0.15 ± 0.12 mg/L), Cd (0.02 ± 0.01 mg/L), and Hg (0.02 ± 0.01 mg/L). Among vegetables, Pb was highest in brinjal (14.48 mg/kg), Cd in spinach (2.37 mg/kg), and As in pumpkin leaf (0.145 mg/kg). Spinach also showed the greatest micronutrient content, with Ca (1164 mg/kg) and K (595.9 mg/kg). The maximum bioaccumulation factors followed the order Cd in spinach (1.26) > Pb in brinjal (0.75) > Hg in tomato (0.15) > Cr = Ni in spinach (0.14) > As in pumpkin leaf (0.03), identifying Cd and Pb as the most mobile elements. The estimated daily intake and health risk indices for Pb (25.68) and Cd (16.81) in children exceeded safe thresholds, indicating significant non-carcinogenic risks. Strong inter-metal correlations (r > 0.70, p < 0.05) suggest industrial effluents as the primary contamination source. Overall, the findings reveal critical Pb and Cd contamination in vegetables from Savar, necessitating stricter effluent regulation and continuous monitoring to ensure food safety and protect public health.